Such devices are used for igniting torches which are fed in a substantially discontinuous manner, or for igniting torches under exceptional conditions, e.g., during well testing, or for igniting a torch as an ultimate security measure when the conventional security means continuously maintained become inoperative due to failure of the gas feeding system pilot burners, or due to disturbance of an electric system, or similar occurrences.
The known torch igniting devices using pyrotechnical cartridges are actuated manually from the ground, and consequently propulsing means are required for propulsing the combustible elements in such a manner that they cross the cone formed by the gases issuing from the torch orifice at an altitude above the ground which in many cases exceeds fifty meters.
The known device have two major drawbacks, to wit:
(a) the lack of precision of the ballistic propulsion according to a path having a pronounced curvature, especially in its effective portion passing through the gas cone, said path being very sensitive to the atmospheric conditions, and more particularly to the variations of the direction of the wind;
(b) the necessity of maintaining the propulsed elements in a state of combustion over a large portion of their path, whereby it becomes inevitable that fragments thereof will fall backward toward the ground while still in a state of ignition.
It is an object of the instant invention to overcome these drawbacks by placing the igniting device at the smallest distance possible from the torch outlet orifice, whereby it is possible to shoot (or fire) straight in a substantially more accurate manner than in the case of the curved shooting path obtained with the known devices; furthermore, the arrangement according to the invention enables to confer on the propulsed elements of the cartridge characteristics which result in a reduced combustion time, and consequently cartridge fragments reaching the immediate vicinity of the torch will have a temperature close to the ambient temperature, whereby any fire hazard is excluded.